This article was co-authored by Patricia Somers, RD. Patricia Somers is a Registered Dietitian in Arkansas. She received her RD from the Academy of Nutrition and Dietetics in 1979.

There are 19 references cited in this article, which can be found at the bottom of the page.

A ketogenic diet (also known as “nutritional ketosis”) is a high-fat, adequate-protein, low-carbohydrate diet. On a ketogenic diet, your brain uses ketones (a byproduct of your fat-burning metabolism) for fuel, instead of glucose.[1] Since humans can burn either glucose or ketones for energy, this change is possible to make, although there is some controversy surrounding ketogenic diets regarding both their efficacy and health benefit.[2] Ketosis keeps your body in a “fasting” or starvation metabolism, and consequently encourages weight loss by burning off fat reserves. While the shift to a ketogenic diet can be difficult initially, you should begin to see results after a few weeks.

Steps

Part 1

Beginning a Ketogenic Diet

1

Talk to your doctor. Although the ketogenic diet is grounded in medical and nutritional fact, there is not a universal opinion in the medical community that the diet is effective for weight-loss. Your personal doctor will be able to advise you if the diet is a good fit for you personally.

Some sources view a ketogenic diet as an effective way to counter the symptoms of certain illnesses — such as epilepsy — rather than a weight-loss diet.[3]

If you are pregnant or diabetic, work with your doctor so they can monitor and adjust your medications while you follow this diet. [4]

If you are type-1 diabetic, seek permission from a doctor well-trained in nutrition before you start this diet.

2

Recognize the possible risks of a ketogenic diet. A ketogenic diet — and putting your body into ketosis generally — presents risks for anyone who suffers from heart or kidney problems.[5] If you are at risk for heart disease or kidney disease, avoid ketogenic diets.

A ketogenic diet prescribes moderate amounts of proteins, and large amounts of fats.

A ketogenic diet will also add strain to your kidneys. Protein-heavy foods increase the amount of calcium in your urine. This, in turn, can strain your kidneys and lead to the development of kidney stones.

3

Start with a general low-carb diet like Atkins to ease yourself into nutritional ketosis. The Atkins diet is heavy on fats and proteins, low on carbohydrates, and will encourage your body to burn ketones for energy. Atkins is a decent “middle ground” between a regular diet (often high in carbs) and a low-protein ketogenic diet.

This step is optional, but may make the transitional period into a ketogenic diet easier.

4

Calculate your “macronutrients.” Macronutrients are nutrients which your body needs in large quantities, and they provide energy in the form of calories. Calculating your macronutrient intake will let you see the current levels of your fat consumption. With this information, you can decide how to reduce your carb and protein consumption, and increase your fat consumption.

There are three types of macronutrients: fats, proteins, and carbohydrates. Fats provide more calories per gram than either proteins or carbs.

There are many macronutrient calculators available online. You’ll need to input your height, weight, daily exercise, and dietary information.

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Part 1 Quiz

When should you avoid trying a ketogenic diet?

If you are pregnant.

Not quite! Even if you're pregnant you might be able to successfully implement a keto diet. Talk to your doctor before you begin to make sure you're still getting the nutrients you need. Try another answer...

If you are at risk of developing a heart disease.

Exactly! If you are at risk of developing heart or kidney disease, don't start a keto diet. This diet will strain your heart and your kidneys, which could lead to serious complications if you're already at risk. Read on for another quiz question.

If you are on the Atkins diet.

Nope! Actually, starting the Atkins diet is a good way to transition from your usual diet into keto. It's not necessary that you start the Atkins diet first, but if you're already doing it, you may be better prepared for a keto diet. Try another answer...

If you are pre-diabetic.

Not necessarily! If you are diabetic or pre-diabetic, you should talk to your doctor before starting a keto diet, but it's not necessarily a bad idea for you. You and your doctor will be able to put together a plan for starting this diet in a healthy, safe way. Try another answer...

Part 2

Adjusting your Diet

1

Eat as much as 20 or 30 grams of carbs daily. If you determine — through a macronutrient calculator — that you currently eat more than 30 grams of carbs daily, look for ways to decrease your carb intake. It’s crucial to avoid carbs on a ketogenic diet, as carbs easily convert into glucose, which keeps your body from burning ketones for energy.[6]

You should only receive about 5–10% of your daily calories from carbohydrates, by eating about 20 – 30 grams a day.[7]

Eat 2 – 8 ounces of protein several times a day. Protein is a necessary part of your diet, and without proteins, you will have very little energy. You may also feel hungrier or develop food cravings throughout the day. However, too much protein will diminish the weight-loss effects of a ketogenic diet.[8]

You should aim to consume about 25 – 30% of your daily calories from proteins.[9]

The amount of protein you eat will vary depending on how much protein you require as an individual. This is often tied to lifestyle, whether active or sedentary.

3

Eat fats with all your meals. Fats are the cornerstone of the ketogenic diet, and will encourage your body to burn fatty ketones for fuel. Typically, calories from fat should comprise 80 – 90% of your meals.[10] (However, you cannot eat unlimited fats on a ketogenic diet; the calories can still add up and cause weight gain.[11]) Examples of fatty foods include:

Organic butter and lard

Coconut oil

Fatty cuts of organic, grass-fed meat.

Egg yolks and full-fat sour cream

Homemade mayonnaise

Heavy whipping cream and cream cheese

Avocados and bacon

Nuts and nut butters

4

Don’t stress too much about calories. Unlike many other weight-loss diets, you do not need to actively keep track of the number of calories in the dishes you eat while on a ketogenic diet. Since a ketogenic diet reduces food cravings throughout the day, you’ll likely be less motivated to eat excess calories anyway.[12]

If you do want to track your calories, use the following breakdown as a guide (assuming that you’ll consume about 1,500 calories a day):[13]

1,050 calories from fat

300 calories from protein

150 calories from carbohydrates

5

Stay hydrated. Once your body is in ketosis, your kidneys will begin to release excess water which your body had been retaining. This retained water is a consequence of a high-carb diet, and once you reduce your carb intake, water retention will decrease as well.[14]

As a consequence, you may need to increase your daily water intake to avoid dehydration.

Headaches and muscle cramps are a sign of dehydration. You may also need to increase mineral intake, especially salt and magnesium, as these are often lost when your body gets rid of retained water.[15]

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Part 2 Quiz

Which foods will you eat the most on a keto diet?

Protein

Not quite! Proteins should make up about 25-30% of your daily calories on the keto diet. Base your protein intake on the amount of activity you do in a day. Not enough protein will make you sluggish and tired, but too much protein can cause weight gain. Click on another answer to find the right one...

Carbs

Nope! On a keto diet, you want to avoid carbs. Only about 5% of your diet should consist of carbs. Pick another answer!

Fats

Absolutely! Fats should make up about 80-90% of your diet. You'll still need to pay attention to what you're eating, because unlimited fats can still lead to weight gain, even on a keto diet. Read on for another quiz question.

Part 3

Losing Weight on Your Diet

1

Use a ketone meter to test whether you are in ketosis. A ketone meter will measure a small sample of your blood, calculate your blood sugar, and will inform you if your body is in ketosis.

Certain ketone meters test urine rather than blood; however, testing your blood is more accurate than testing your urine.

Ketone meters are commonly for sale at drug stores, and also online.

If you are in ketosis, your body will burn its fat reserves, and you will begin to notice weight loss.[16]

2

Look for ketosis symptoms (also known as “keto flu”). Within three to seven days of starting the diet, you may notice symptoms like: strong-smelling breath or urine; slight nausea; high energy and mental clarity; fatigue; or diminished appetite with no cravings.

If these symptoms last longer than a week, or increase in severity, you should visit your doctor. Severe nausea can lead to vomiting and dehydration, which are unhealthy when continued for multiple days.

Many of these symptoms will vanish once you become keto-adapted.

This symptom analysis can be performed in place of testing, if you are limited financially or do not want to test your blood or urine.

3

Notice that your health has improved (after a few weeks). This should also be accompanied by weight loss, and any bloating or inflammation which you had previously experienced will have improved greatly.

Ketogenic recipes are readily available online. Search online for various keto-friendly sites.

Search in Pinterest (or similar apps) for good ketogenic recipes.

Common recipes include rich “fat bomb” desserts, low-carb sandwiches, and light meals with avocado and salmon.[17]

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Part 3 Quiz

True or False: Keto flu symptoms should last the entire time you're on the keto diet.

True

Nope! If your keto flu sympoms last for more than a week, see a doctor. You might be feeling nauseous, fatigued, or have strong-smelling breath or urine during the keto flu. Guess again!

False

Yes! If your keto flu symptoms last for longer than a week, you need to see a doctor to get some tests done and consider if the keto diet is right for you. Keto flu symptoms should dissipate after you become keto-adapted. Read on for another quiz question.

Tips

The difference between this diet and a general low-carb diet is that low-carb diets generally promote high protein. But, for some people, high protein eventually starts converting to glucose and reduces weight loss. A moderate-protein, high-fat diet works better for weight loss in these cases.

Some people do a Fat Fast to kickstart their ketogenic diet. Do this only if you are already following a low-carb program.

Consider a ketogenic diet especially if you: are diabetic, are hypoglycemic, have insulin resistance, if you gain weight in your stomach area, or if you gain weight on typical low-calorie, low-fat diets.

A ketogenic diet has been shown to reduce the symptoms of epilepsy in children.[18]

Warning

Nutritional ketosis should not be confused with ketoacidosis, a dangerous diabetic condition.[19]

You may experience some hair loss when beginning a Ketogenic diet. This is because your body is adjusting to your diet change. Consult a doctor if your hair loss persists after 3 months on this diet.

If you want to start a ketogenic diet for weight loss, limit how many carbs you're eating so they make up only 5-10% of your daily caloric intake. You should also include protein in your diet, which will help you avoid food cravings throughout the day. Aim to eat 25-30% of your daily calories in protein. The majority of your diet should be made up of fats, so eat a lot of foods like avocados, nuts, fatty meats, and egg yolks. If you eat like this for several days, your body should enter ketosis and start shedding water weight. To learn more about the risks of a ketogenic diet from our Dietitian co-author, keep reading!

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Article Info

This article was co-authored by Patricia Somers, RD. Patricia Somers is a Registered Dietitian in Arkansas. She received her RD from the Academy of Nutrition and Dietetics in 1979.